The applications of activated cyclopropanes to total syntheses of pyrrolizidine alkaloids and mitomycins will be investigated. The strategy involves opening such labile stystems with intramolecularly placed nitrogen nucleophiles. These cyclopropane ring openings then are followed by lactamization to afford functionalized heterocycles suitable for further elaboration. Epoxide openings by equivalents of CH2CO2H will be pursued. This operation coupled with alpha-methylenation of the resultant lactones provides a workable route to natural products which have been shown to possess antitumor properties. Particular targets will be eriolangin and coriolin. BIBLIOGRAPHIC REFERENCES: S. Danishefsky, P. Schuda and K. Kato, "Studies in the Synthesis of Vernolepin - A Diels-Alder Approach to Angularly Functionalized AB System, J. Org. Chem., 41, 1081 (1976). R.K. Singh and S. Danishefsky, "The Cyclopropane Route to Trans-Fused-Gamma-Lactones", J. Org. Chem. 41, 1668 (1976).